Re: [PATCH 2/3] Add new function ip_get__assigned_addresses_from_net()

Hi,

Am Sa, 24. Feb, 2018 um 12:53 schrieb Michael Tremer michael.tremer@ipfire.org:

On Fri, 2018-02-23 at 11:05 +0000, Jonatan Schlag via network wrote:

...

This function is neede by IPsec to set the routes correctly. We can now now find a source IP for a given net. This way is ugly because the source IP is unpredictable if we get multiple IPs.

Signed-off-by: Jonatan Schlag jonatan.schlag@ipfire.org

src/functions/functions.ip | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+)

diff --git a/src/functions/functions.ip b/src/functions/functions.ip index 3b43da7..ef40bcc 100644 --- a/src/functions/functions.ip +++ b/src/functions/functions.ip @@ -205,3 +205,28 @@ ip_address_del() {

return ${EXIT_OK} }

+# Get all currently assigned addresse for a given network +ip_get_assigned_addresses_from_net() {

• local net=${1}
• shift
• local args="$@"
• assert ip_net_is_valid ${net}

I think this assertion isn't needed because "ip" will check this and just throw an error.

But can we catch the error in a nice way? I could have a look at this but using $? should be harder then to use our normal functions.

...

• local line
• local ips

It would be nicer if the "ips" variable would be called "addresses" because that is the term that we actually use most of the time.

Ok

...

• # We read the output of $(ip addr show to ${net} ${args})
• while read -r line; do

• # We are only interested in lines which start with inet or
  

inet6

• [[ "${line}" =~ ^(inet6 |inet ) ]] || continue
  

• # We need the second word the line
  

• line=(${line})
  

• list_append "ips" "$(ip_split_prefix "${line[1]}")"
  

You could also achieve this by passing the line argument up to the first space and use the "%" and "#" parameters in the brackets.

I am not sure if the conversion to the array has any implications.

So how can we make shure that this has no implications?

...

• done <<< "$(ip addr show to "${net}" ${args})"
• # We sort the list to get the lowest IP as first item
• print "$(list_sort ${ips})"

You don't need to call print here. This will create a subshell for the list_sort call, but list_sort already prints the output, so you can just write:

list_sort ${ips}

That will be a lot faster.

Ok

...

+}

-Michael